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Staging canola for swathing or pre-harvest desiccation is critical to maintain high quality seed and maintain yield. Ideal swath timing is when 60% of seeds on the main stem have turned colour, meaning 60% of all the main stem seeds are showing some form of colour (yellow, brown, black) other than green.

For 60% seed colour change, the bottom third of the main stem of the plant will have totally brown/black to purplish seeds, the middle third will have turned, or be showing some spots of colour, and the top third are green. The green seeds must be firm and should roll between your fingers without squishing. At this stage, the average moisture content is about 30%.

Producers are reminded that more than one area in a field will need to be assessed for seed colour change. Relying on a visual assessment of canola pod colour alone will not provide an accurate estimate of crop stage. In many cases, the outside of the pod colour can turn brownish yellow but seeds inside may still be green.

Earlier swathing tends to lock in green chlorophyll in underdeveloped seeds, reducing oil content and potentially causing marketing issues. Canola can be swathed in the 30-40% seed colour change stage to manage a large number of acres ripening at the same time, but producers should be aware that swathing at this stage can cause yield losses up to 8%.

Dry growing conditions and damaging weather have impacted canola development across Manitoba in 2018. Evaluating canola fields for evenness and uniformity is important to selecting the right time to swath or desiccate the crop. If growth conditions allowed large patches of delayed emergence, or hail set back crop development, estimating the patch size and managing the crop according to the largest percentage area is a good recommended practice.

In general, a pre-harvest aid (glyphosate and Heat LQ) should be used to increase plant tissue drydown and kill green weeds. The correct stage is 60-75% seed colour change. Expect to harvest the crop 1-3 weeks after spraying, similar to the time expected between swathing and harvesting.

A desiccant with the active ingredient diquat works more quickly, forcing removal of crop moisture. A fast-acting product, expect to harvest 4-7 days after application. Target a minimum of 90% seed colour change, as diquat will lock in any remaining green chlorophyll in the seed.

Points to Consider

Caution is advised when swathing or desiccating a canola crop, since that is considered growth and development termination, according to pre-harvest interval (PHI) standards. Know the length in days PHI of the fungicide and/or insecticide used on the crop; swathing or desiccating should not take place before that PHI window closes.

Because of our experience with crops and weeds, it’s no surprise that the general public often turns to agronomists for plant identification and management advice. And it’s usually about this time of year – when Ontario puts out giant hogweed advisories and big white umbels are in bloom across Manitoba – that these calls start to pour in.

Cow Parsnip

Fortunately, it’s probably not giant hogweed (Heracleum mantegazzianum) since that invasive species has yet to be found in our province. It’s more likely another member of the carrot family – cow parsnip (Heracleum maximum). Unlike its giant cousin, cow parsnip is native to Manitoba and non-invasive. It’s also very attractive to pollinators.

But even though it’s probably not giant hogweed, it’s still best not to touch it. Because, much like its giant cousin, the sap of cow parsnip may cause dermatitis when in contact with exposed skin. Symptoms include photosensitivity, a rash and/or blisters. Reactions to cow parsnip sap are generally much less severe than those to giant hogweed sap.

Rust in sunflower is caused by the fungus Puccinia helianthi, which overwinters on plant stubble and produces five spore‐stages throughout the year. Early in the season, orange rust pustules appear on the upper surfaces of cotyledons of seedlings and volunteer plants, with later infections moving to the underside of the leaf (Figure 1). The most yield-damaging stage occurs in late July to early August, when symptoms of infection show up as dusty, dark brown pustules on leaf surfaces, petioles and flower bracts (Figure 2). As the disease develops, black teliospores form, overwintering on the crop residue.

Figure 1: rust on leaf underside (photo: MB Ag)

Figure 2: Rust on leaves, stem. Wilting plants (photo: MB Ag)

Sunflower rust becomes a more severe issue in later-planted crops, or crops with weaker genetic resistance. Warm, moist weather favours rapid multiplication of rust spores, and windblown spores can travel quickly from field to field. Early stages of sunflower rust in 2018 have been observed in the Cypress River area the week of July 3rd.

High plant populations and dense, leafy canopies allow humid conditions to remain in the crop throughout the day, compounding injury from rust spores.

Scout sunflower fields regularly to monitor the development and stage of rust infection. Watch for dense clusters of brown, powdery pustules scattered over all plant surfaces. Orange-brown ‘dust’ on clothing after being in a sunflower field is a key indicator that rust is present, and more careful scouting is needed. Withered lower leaves are an indication that the surface is heavily infected.

Controlling rust after infection is primarily done using triazole-based and strobilurin-based fungicides. Recommended action in rust-infected crops is to use a fungicide from the triazole group after the first onset of symptoms, at the 2-3% pustule coverage on the upper four leaves at flowering (R5). Strobilurin-based fungicides act more as a ‘protectant’, applied earlier before widespread infection occurs.

Diseases: New clubroot cases have been confirmed in the Rural Municipalities of Lorne and Dufferin.

Insects: Scouting for bertha armyworm continues with some reports of insecticide applications. Spider mites being noticed in some soybean fields. Grasshopper populations are variable. For full report see Insect & Disease Report – August 1, 2018

Crops are advancing rapidly with the warm and dry conditions. Rain is needed in most areas to sustain crops and replenish soil moisture. Harvested has started in winter cereals, barley, and peas. Swathing or pre-harvest applications have started in early seeded spring cereals and canola. Fist cut hay is nearing completion; yields are below normal. Regrowth has been limited due to dry conditions, and a second cut may not be possible in some areas. For full report see Crop Report – July 30, 2018

Diseases: The second case of clubroot in canola this year has been reported. Disease surveys in soybean and wheat are ongoing and disease levels are low overall.

Insects: Overall insect concerns in field crops are relatively low. There are still some areas where grasshopper levels are being watched. Spider mite levels are being monitored in some soybean fields in the Central region. No soybean aphids have been found in Manitoba yet this year. Concerns over diamondback moth levels in the Eastern and Central region seem to have diminished. Full report at Manitoba Agriculture Insect & Disease Report

Hot temperatures and rainfall last week has advanced crop quickly with earlier than normal harvest dates expected. Winter cereals are at hard dough stage and starting to ripen. Spring cereals range from milk stage to ripening. Moisture stress seen in fields across Manitoba where rainfall has been inadequate, areas with lighter textured soils have prematurely ripening crops. Hay yields are below normal and producers are indicating rainfall needed for regrowth to allow for second cut and continued pasture grazing. For the full report see Manitoba Agriculture July 23 Crop Report

Wheat growers are nearing decision time on whether to supplement their wheat crop with nitrogen for protein enhancement.

Currently it is suggested that if the yield potential of the wheat crop looks good, and higher than for the N rate initially supplied (i.e. at 2 lb N soil and fertilizer per bu), consider trying a treatment. And check with your marketing consultant whether market signals suggest a shortage of high protein wheat being harvested elsewhere.

Early season root rot has been reported in both soybeans and sunflowers. Current insects to watch include grasshoppers, diamondback moth and thrips on barley. Read full report at Insect & Disease Report – June 27

There are a few points to remember when considering a fungicide application for sclerotinia in canola this year:

In order for sclerotia to germinate and produce apothecia, they require at least 10 days of moist soil conditions (surface soil – as we aren’t concerned with sclerotia that are buried more than an inch or two below the surface).

Spores cannot infect leaves and stems directly – they grow on senescing tissue (i.e. canola petals) and then spread to the leaves and stems.

Dew/rainfall after petal drop is required for the pathogen to spread from the infected petals to the stem. Petals that dry up in leaf and branch axils without any moisture will not spread the infection.

The recommended timing for a fungicide application for sclerotinia management in canola is 20-50% bloom. This is because typically the canopy has filled in after 50% bloom. Petals can still be infected after 50% bloom, but when they fall, they tend to land on upper branch axils. Infection that only affects minor upper branches will not have a large impact on yield. If a crop is stagey or the canopy thin, infected petals may land on lower leaf and branch axils even after 50% bloom and infect the main stem. As long is there are petals present on the plants there is potential for infection to occur, the question is where will those petals land when they fall?

Crops are advancing quickly in Manitoba. Dry conditions continue throughout the province. Herbicide applications continue in some parts of the province, but are generally wrapping up. Fungicide applications are on going, largely in winter and spring wheat for management of fusarium head blight. First cut haying operations continue. Yields range from normal to below normal depending on moisture conditions.

Bacterial blight has been reported in many oat fields in south-central and south-eastern Manitoba. Environmental stress symptoms have also been reported in oats. Fungicide applications in spring wheat and canola are being considered and weighed against the current environmental and microclimatic conditions.

Early-season concerns, such as flea beetles on canola and cutworms are coming to an end. Most of our potential insect pests of mid-season have not been detected at high levels yet.

Parts of the Southwest and Central regions experienced storms this past week, including heavy rainfall, strong winds and hail. Across the regions, warm temperatures are helping crops advance quickly, some regions that did not receive rainfall are concerned over continued dry conditions. Herbicide applications continue and fungicide applications for fusarium head blight have begun. First cut haying continues.

Hail has been reported in several areas of Manitoba, and due to the size of the hail and duration of the storm, crops were affected in some areas. Assessments of damage will occur over the next few days. The amount of loss expected from a hail event depends on the severity of hail, crop type, and the growth stage of the crop.

Spring Wheat – is least susceptible to hail damage prior to stem elongation since the growing point is below the soil surface and will likely not be damaged. Hail damage during jointing or in the boot stage is difficult to assess. Spikes can still pollinate and fill, and regrowth from new tillers can occur. The more advanced the wheat is at the time of hail the greater the yield loss. The greatest yield reduction from hail occurs in the milk stage.

Oats and Barley – will tiller and recover better from hail than wheat, especially prior to the boot stage. Grower experience has demonstrated that barley hailed severely in the boot stage has recovered to produce 70-80% of normal yield. Crop hailed prior to the boot stage should be left if stems or green tissue remains.

Corn – early season hail occurring when the growing point is still below the soil surface will result in very little yield loss. At the 6 leaf stage the growing point is above ground, but leaf loss without damage to the growing point has a small impact on yield. Yield loss as a result of hail can be estimated by determining percent leaf defoliation (Table 2). Leaf area removed and leaf necrosis need to be considered, while damaged green leaf tissue should not be included. Assess leaves 7-10 days after a hail event, so that living and dead tissue can be easily distinguished.

Assessing Damage – New growth should be evident within a few days after a hail event. Assess crop to evaluate new crop growth. Yield potential of a damaged crop will depend on rainfall and temperatures in the next 30 days after hail damage.

When applying post-emergent herbicides, proper corn growth staging is extremely important. Herbicide labels may refer to plant height, crop growth stage, or both when listing crop stage timing. Farmers and agronomists need to accurately stage corn plants to ensure that herbicides are being applied at the correct stage. Some common methods of determining corn growth stage are listed below.

Figure 1: Corn Staging Diagram

Figure 2: Live Plant Corn Staging

Corn Height Method – Measure from the soil surface to the highest point of the arch of the uppermost leaf whose tip is pointing down. Don’t measure to the “highest point” on the plant, which is often the tip of the next emerging leaf above. Refer to Figure 1/2 on how to correctly determine the height of a corn plant. Corn height varies due to growing and crop management conditions, and is not the most accurate way to stage corn.

Leaf Over Method –Count the number of leaves, starting from the lowest (the coleoptile leaf with a rounded tip) to the last leaf that is arched over (tip pointing down). Younger leaves that are standing straight up are not counted. In Figure 1/2, the corn plant would be at the 4 leaf stage using the leaf over method.

Leaf Tip Method – Count all leaves, including any leaf tips that have emerged from the whorl at the top of the plant. In Figure 1/2, the corn plant would be at the 6 leaf stage using the leaf tip method.

Leaf Collar Method (V-stage) – Count the number of leaves with visible collars, starting from the lowest (the coleoptile leaf with a rounded tip) and ending with the uppermost leaf with a visible leaf collar. This method is the most common staging system and involves dividing the plant development into vegetative (V) and reproductive (R) stages. The leaf collar method is generally also the easiest to use, and related better to the physiological stage of the plant and therefore to the effects of herbicides. In Figure 1/2, the corn plant would be at 3 leaf stage (V3) using the leaf collar method.

See Dry Weather Weed Control on Manitoba Agriculture website for more details and complete recommendations and cautions.

Dry weather means both weeds and crops shift gears. Weed spectrums can be different, post-emergent herbicides can be less effective because weeds may have smaller leaves and/or thicker cuticles (waxy layer) that slows the penetration of herbicides.

Some herbicides withstand dry weather better than others so choose your product carefully. Here are some general guidelines on weed control during a dry period.

Seeding progress estimated at 99% complete across Manitoba. Widespread and warm temperatures have resulted in rapid crop growth. Herbicide applications continue as field conditions allow and crop and weeds reach the appropriate stage. Flea beetle activity reported in canola and cutworm feeding reported in both canola and sunflowers.Pasture and hayland conditions have improved, most cattle are now on pasture. See the full June 4, 2018 CROP REPORT

Seedling diseases are showing up in early seeded soybeans. Insect concerns are flea beetles in canola, some reports of cutworm feeding and report on insect monitoring for Diamondback moth. For the full report see most recent Manitoba Insect and Disease Update

Or could it just be environmental stress due to frost injury, lack of moisture and drying winds?

A tissue test is needed to confirm copper deficiency as the culprit.

Studies in Manitoba compared three timings of foliar copper sprays on deficient spring wheat and showed that copper deficiencies and impact on yield can be severe or slight and can vary from year to year.

Timing and application method are important to regain yield! For more information and pictures on copper deficiency, see the full .pdf copy of Copper Deficiency in Wheat

Already we are hearing of spotty emergence with cereal crops in Manitoba. Possible culprits may be dry seedbeds, poor quality seed, seed depth, herbicide residues, or seed placed fertilizer injury.Past Prairie studies suggested a 15% stand reduction was tolerable for cereals since surviving plants tillered and filled in the stand. But maturity is less uniform and is delayed up to 4 days.

How might one confirm seedplaced fertilizer injury? Close inspection can show a range of symptoms:

1. Seeds that imbibed water but did not develop any root or shoot

2.Seeds that developed shoots but no roots

3.Seeds that developed root and shoot but leafed out below ground

4.Those that did germinate and emerge (about 44%) were ½ to 1 full leaf stage behind normal seedlings in the low fertilizer strip.

In other crops injury can show as:

Canola – seeds just do not germinate and remain intact. Fields simply appear to have very poor crop establishment.

Soybeans – stands may be injured, especially with wider row spacing and on sandy soils under dry conditions.

Seeding is nearing completion for the 2018 season in Manitoba, with progress estimated at 94% complete. Most areas of the province received rainfall, although amounts were variable. Additional precipitation is needed in many areas. Recent rains combined with warm temperatures have resulted in rapid germination, emergence, and crop growth. Herbicide applications are underway, and are expected to become a priority in the coming week. Flea beetles activity is reported throughout the province, with control measures necessary in some fields. For more information see the full May 28 CROP REPORT

Seeding operations continue across Manitoba with provincial seeding progress estimated at 80% complete. Winter injury has resulted in some reseeding of winter wheat in the Central, Eastern, and Interlake regions. Dry conditions have resulted in slow growth and difficulties assessing injury. Pasture and forage growth has improved in areas that received precipitation, but supplemental feeding is still required in most areas. For the full report see http://www.gov.mb.ca/agriculture/crops/seasonal-reports/crop-report-archive/crop-report-2018-05-22.html

Provincially, seeding in Manitoba estimated to be 55% complete. Cereals, peas, and some early seeded canola are starting to emerge. Most areas dry and need rain to aid in crop emergence and pasture regrowth. For more information and regional reports see Manitoba Agriculture CROP REPORT, May 14

Favourable weather and field conditions have allowed seeding operations to get underway in most areas of Manitoba. Soils are becoming dry, rain needed to aid in crop germination and emergence. Winter cereal crops are in generally good condition, winterkill is being assessed in some areas. Pasture and hay fields are slow to resume growth, but are starting to green up. For more details on regional conditions see May 7th Crop Report.

Surface broadcasting of nitrogen (N) fertilizers has become popular to increase operational efficiency – increasing the speed of seeding and reducing risk of seed injury. But, in a dry spring with limited rain prospects, growers may choose not to till and avoid further drying out seedbeds. Then growers must consider the risks of nitrogen volatilization loss and take precautions when risk is high.

Volatilization of ammonia (NH3) from urea or the urea portion of UAN (28-0-0) affected by several factors and can be increased under specific situations.

For more details on the risk factors and ways to minimize losses, see full .pdf

More topics on soil fertility can be found on Manitoba Agriculture’s Soil Fertility webpages.

There is no single best way to fertilize corn in Manitoba. The 4 most common N application methods are spring broadcast and incorporated, fall banded, banded at seeding and preplant banded.

In a dry spring like 2018, broadcasting and incorporating fertilizer before seeding, risk drying out the seedbed. Many farmers, especially on clay-textured soils prefer not to disturb their seedbed in the spring and so prefer to fall band their N. And although spring preplant banding is a very efficient way to place nutrients for a corn crop, it comes with some particular cautions – thinning and seedling injury.

With a lack of seedbed moisture, there are justified concerns about seedplaced fertilizer injury to canola and other crops. How safe is sidebanded nitrogen? Research studies by Dr. Cindy Grant documented considerable canola stand thinning when high rates of sidebanded urea or UAN solution were applied. Agrotain (AT) served to reduce stand injury, but is no longer supported for this use by the manufacturer.

Points:

Stands were thinned at even modest N rates, on a clay loam soil. At high rates stands were reduced to 50%

Crop growth compensated for reduced stands and generally produced as good a yield as the Agrotain protected stands, except at the highest rate.

For more detailed analysis and discussion on the issue see the full .pdf

More topics on soil fertility can be found on Manitoba Agriculture’s Soil Fertility webpages.

Spring 2018 has brought many questions about seedplaced fertilizer rates for canola. Several factors are causing concern:

Drier soils – which increase the risk of seed toxicity

Desire to apply sufficient P to meet crop removal – since many fields have seen decreasing P levels due to high yield. P removal is about 1 lb P2O5/bu, so high yield potential fields are looking at high P replacement rates.

Increased use in low disturbance, low seedbed utilization (SBU) drills. Many new openers are arriving on the scene, which are “close-to-seed” sidebanding for which one may need to consider as seedplaced.

Desire by growers to reduce seeding rates for cost savings. Most research studies investigating seedplaced fertilizer injury were seeded at some 150 seed/m2, about double what some farmers are now targeting.

For more detailed analysis on the issue, see the full text in .pdf format

As of August 1, 2018, 25 Canada Western Red Spring (CWRS) varieties and 4 Canada Prairie Spring Red (CPSR) varieties will be moved into the Canada Northern Hard Red (CNHR) class. Prior to putting seed in the ground, consult the Canadian Grain Commission’s variety designation list to see if the variety you are planning to grow will be changing classes before harvest.The complete list of varieties transitioning to CNHR is available at: https://www.grainscanada.gc.ca/consultations/classes-en.htm

The modernization of the wheat class system revised the parameters of the CWRS and CPSR classes to ensure that wheat varieties in these classes met strict quality guidelines. The varieties transitioning from CWRS and CPSR to CNHR do not meet the quality parameters of their current class. The CNHR wheat class was created to allow farmers more flexibility in the wheat varieties they grow while preserving the quality of the CWRS class. Wheat varieties in the CNHR class such as Faller, Prosper, and Elgin ND, have slightly lower protein than CWRS wheats but are higher yielding.

Extremely cold temperatures were experienced throughout Manitoba at the end of December and beginning of January. The cold temperatures combined with limited amounts of snow cover have many winter wheat producers thinking about winter survival.

Manitoba Agriculture’s Ag Weather Program has been monitoring soil temperatures in winter wheat fields for a number of years. There are currently three weather stations measuring real time soil temperatures in winter wheat fields at Alexander, Dauphin, and Kleefeld. The data collected from the weather stations is made available to the University of Saskatchewan and Western Ag Labs for their Winter Cereal Survival Model, available at: https://www.wheatworkers.ca/wcsm.php. The Winter Cereal Survival Model compares the cold tolerance of winter wheat varieties to the daily average soil temperature at crown depth (about 1”).

Plotting the soil temperatures against hardiness curves can give an early indication if there is a concern for winter injury or winterkill. Factors that can impact the level of cold hardiness of the plant include weather, fertility, seeding date, and seeding depth. In Manitoba, the majority of winter wheat acres would likely be considered to be well-hardened. The figure below shows soil temperatures at 1” depth in three winter wheat fields in Manitoba, plotted against three hardiness curves.

Soil temperatures in Alexander and Dauphin dipped below the low hardiness curve, but have not approached the mid and high-hardiness curves at this point. To assess the level of risk on your farm consider how well-hardened your field may be and check your fields for level of snow accumulation. It is still early in the season, so check back in on the Winter Wheat Survival Model throughout the winter to get an idea of the risk of winterkill in your area.

It is important to know the grade and dockage of your grain prior to marketing to ensure that you receive a fair price for your grain. The Canadian Grain Commission (CGC) provides the following grain grading services:

The Canadian Grain Commission’s Harvest Sample Program
The Harvest Sample Program provides unofficial grade and quality results at no charge for most grain, oilseed, and pulse crops. Samples are submitted at harvest time and results are emailed to the producer. Producers who have previously signed up for the Harvest Sample Program will receive a Harvest Sample kit annually. For more information on the Harvest Sample Program or to sign up visit the CGC website.

Producer Request for Inspection Services
Producers that did not participate in the Harvest Sample Program but would still like to receive a grade for their grain can submit a sample to the CGC for a fee. It is important to submit a representative grain sample as the grade received should accurately represent grain stored in a bin. Instructions on representative grain sampling can be found on the CGC website. Once you have a representative sample, complete the request for inspection services form I-106 and send the sample by mail or courier to the CGC Weyburn office for inspection. Instructions and additional tests available are found on the form.

What steps can be taken when you disagree with an elevator’s assessment of your grain’s grade and dockage?As legislated under the Canadian Grains Act producers can dispute a licensed primary elevator’s assessment of their grain. If you do not agree with the assessment of your grain at the time of delivery, you can ask that a representative sample of your grain be sent to the CGC for inspection. Payment for your grain will be subject to the inspectors grade and dockage. For more information, visit the dispute your grain grade section of the CGC website.

The vast majority of corn in Manitoba is in the bin, but what about those few fields that may not be harvested yet? In some cases weather conditions may have made it difficult for farmers to harvest corn in the fall, but some farmers may decide that the corn moisture level and costs associated with drying mean that it is more economical to leave corn in the field to let it dry down naturally over winter.

Just how much dry down can be expected over winter? The amount of drying that occurs in the field depends on the corn maturity, variety, and moisture content, as well as environmental factors such as temperature, humidity, solar radiation, and wind speed. Field drying is extremely slow in the winter, and corn will only dry to about 20 to 21% moisture content. In a typical year, it is expected that corn will dry approximately 11-12% in October, 4-5% in November, and just 2% per month in December and January (Table 1).

Table 1. Estimated corn field drying

Month

EMC (%)*

GDD

PET (in.)

Estimated Drying (% pt.)

Month

Week

Sept

15

250-350

4-5

18

4.5

Oct

16

100-125

2.8-3.5

11-12

2.5

Nov

19

20-30

0.8-1.2

4-5

1

Dec

20

0

0.5-0.8

2

0.5

Jan

21

0

0.5-0.8

2

0.5

Feb

21

0

0.5-0.9

3

0.8

Mar

19

0

1.3-1.6

5

1

Apr

16

50-90

3.2-4.5

16

4

May

14

200-300

6.5-8.5

30

7

*EMC – equilibrium moisture content, GDD – growing degree days, PET – potential evapotranspiration 1EMC is the moisture content to which corn will dry and is based on air temperature and relative humidity

Risks of overwintering corn Heavy snowfall during the winter can cause significant amounts of lodging resulting in yield losses. Root and stalk strength should be taken into consideration when deciding if a field should be overwintered. Research conducted at the University of Wisconsin examined corn yield loss during the winter (Table 2).

This researched showed that in 2000, a year with heavy snow cover, yield loss was much greater than in 2001, a year with very little snow cover. Standing corn may result in more snow catch and slow soil drying in the spring, which could delay planting.

Table 2. Percent yield loss of corn left standing in the field through winter at Arlington, Wisconsin.

Corn can be harvested throughout the winter if conditions are cool and there isn’t much snow. If stalks stay standing throughout the winter, and ear drop and wildlife damage are limited, corn can get through the winter without much yield loss. Yield loss throughout the winter will vary by hybrid and environmental conditions.

If you are planning to over winter corn please contact your local MASC agent.

September 5, 2017 – Pinawa, Winnipeg, Whiteshell and Steinbach overnight forecasts, Environment Canada is stating there is a risk of frost.

Whether or not there is yield loss in soybeans depends on two factors. One is how cold it gets and how hard it freezes. We won’t know the story on that until tomorrow. The other factor is the growth stage the soybeans are at and that is determined by examining the pods on the plant. It is all about the pods, so don’t get distracted by the condition of the leaves. The more advanced/mature the soybeans pods are, the less the potential yield loss.

Manitoba Pulse and Soybean Growers has a maturity guide on their website that will provide you with excellent pictures and descriptions of the growth stages we are now seeing in our fields. Use it as your guide in determining where your beans are at. Click on the link below to access:

You will always find some variation around predictions of yield losses due to frost in soybeans. This is to be expected. There is no absolutely right answer. No crop is uniformly at one growth stage and every frost event is unique in how it plays out. The information above is merely meant to serve as a guide.

Frost anytime before the sunflower crop reaches physiological maturity (R9) can cause damage. Once sunflowers reaches the R7 stage (ray petals have dropped, back of head starting to turn yellow), sunflower can withstand temperatures as low as -4° C, but temperature, duration and crop stage will influence the type and amount of damage.

A killing frost in sunflowers is considered to be -4 to -5° C for 6 or more hours, as this low temperature for the extended period is required to penetrate the thick layer in the back of the sunflower head and start the dry down process. See attached bulletin for more details:

Canola is coming off and seeding of winter wheat is upon us. While acres of winter wheat have dropped in recent years, there are good agronomic and economic reasons to include winter wheat in your crop rotation. Get your winter wheat crop off to a great start this fall by considering these seeding tips.

Stubble – Winter wheat needs a good snow cover of 4 inches or more to ensure winter survival. This can be accomplished by direct seeding into tall, dense standing stubble. Stubble disturbance during harvest and seeding should be minimized to ensure that a good amount of stubble is retained for snow trapping.

Weed control – It is important to control green cereal vegetation prior to seeding winter wheat to eliminate the risk of wheat streak mosaic virus. Winter wheat should not be seeded near immature spring cereals and all cereal volunteers should be controlled at least 2 weeks before seeding winter wheat.

Variety selection – Yield is generally the first factor considered when choosing a winter wheat variety, but farmers should also compare varieties for agronomic factors such as standability, disease resistance, maturity, and winter hardiness. Seed Manitoba is an excellent starting place for evaluating the current and new varieties coming to the marketplace (www.seedmb.ca).

Seeding date – Healthy, vigorous plants must be established before freeze-up to attain maximum cold tolerance. The goal is to have plants with a well-developed crown and about 3 leaves going into the winter. The crown is the area from which the plant regrows in the spring. Research has demonstrated that seeding during the period from late August to early September (approximately August 25 to September 10) consistently produces the best crops in terms of both yield and quality.

Seeding depth – Winter wheat should be seeded less than 1” deep even when seedbeds are dry. Shallow seeding allows the seed to take advantage of fall rains, and as little as 1/3” of rain is enough to successfully establish winter wheat.

Seeding rate – Seed at higher rates to ensure a dense, uniform plant stand to enhance weed competition, winter survival, and yield potential. Typically, farmers should be aiming for a final plant stand of 30 plants per square foot in the fall. Calculate the seeding rate needed to obtain the desired final plant stand with the formula below:

In 2016, some of John Heard’s corn nitrogen plots yielded over 200 bu/ac with the University of Manitoba plot combine. He refused to report such astounding yields until the electronic weighing system had been verified with bagged and weighed yields.

Likewise scrutiny and calibration is required when using yield monitors for strip trial tests. In 2016 Manitoba Agriculture and Manitoba Wheat and Barley Growers Association compared harvest weights from strip trial yields in on-farm-tests looking at nitrogen and wheat protein. Several farms had scaled grain carts in addition to their combine yield monitor (Figure 1) and all plots were measured with a weigh wagon. Figures 2 and 3 shows the trends of grain cart and yield monitor data versus the weigh wagon yield (solid line).

Farm A – with scaled grain cart used to calibrate yield monitor. Yields follow trend of weigh wagon weights and are within 2 bu/ac.

Farm B – A seldom calibrated yield monitor with yields not corresponding to weigh wagon weights and up to 6 bu/ac less.

Yields from a perfectly calibrated yield monitor and grain cart would fall on the black line in the graphs above. Farmers with accurate, scaled grain carts were usually calibrating their yield monitors in each field and producing very similar results as the weigh wagon (such as Farm A). Those that were calibrated on earlier fields or earlier in the season were unable to measure the subtle yield differences in this study and may lead to erroneous conclusions.
So if yield monitors are being used to measure strip trial yields, I encourage growers to calibrate often with their scaled grain carts or a weigh wagon if available. The measurements we made were in dry wheat but if crop strips are of varying moisture content, more frequent calibration may be warranted.

Several of our maturing crops are now exhibiting deficiency symptoms that are too late to correct, but important to address for next year.
Potassium (K) is often overlooked in much of Manitoba due to our naturally high K levels in clay and clay loam soils. But deficiencies on lighter textured soils are increasing – particularly with soybeans.

Potassium deficiency often shows up during pod and seed fill, since soybeans remove 1.4 lb K2O/ bu of grain, the heaviest rate of removal of any grain crops. As K is translocated out of leaves to fill seeds, the deficiency shows up as yellowing and later necrosis of the leaf margins.
Sometimes odd strips occur of alternating deficient and normal soybeans occur in fields. These are often related to a previous canola or cereal swath that has had the K leach out of the swath into the soil beneath, and hence marginally increasing K supply in that strip.
If either of these symptoms are observed, a K deficiency can be readily identified with a traditional soil K test and a recommendation will be made for future K fertilization.

Like many carrot family weeds, spotted water hemlock populations in Manitoba have been spreading, likely due to wet conditions over the last several years. Managing populations in hayland and pasture is recommended since hemlock species are extremely poisonous to humans and livestock.

Identifying Spotted Water Hemlock

Proper identification is important since spotted water hemlock looks similar to water parsnip, another carrot family weed commonly found growing in wet areas across the province.

Managing Hemlock

All parts of the hemlock plant are poisonous. Young leaves and re-growth after treatment may attract livestock, especially if other food sources are limited or less palatable. Access to water hemlock by livestock should be restricted while populations are being managed.

The following methods can be used to control or suppress spotted water hemlock in hayland and pastures:

Hand pulling (wear gloves!). Pulled plants can be left in the sun to dry. Once dry, plants can be disposed of in an area away from people and livestock.

Repeated cutting or mowing.

Herbicide spot treatment or foliar application. Glyphosate, 2,4-D and picloram have activity on water hemlock. Refer to the label for grazing and haying restrictions.

Cultivation.

Feeding Hay and Greenfeed with Water Hemlock to Livestock

Feeding hay with some water hemlock in it to livestock is okay, according to research from the US, as long as the hay (and hemlock) is thoroughly dried. The curing process allows the toxins in water hemlock to dissipate, reducing the risk of livestock poisoning. Hay with water hemlock should either be fed last to allow for maximum dissipation of the toxins or occasionally interspersed with hay not contaminated with water hemlock. If possible, contaminated hay should not be fed continuously to pregnant livestock, as there is evidence that chronic exposure to water hemlock toxins can result in birth defects.

Unlike hay, greenfeed contaminated with water hemlock should not be fed to livestock or used for silage or baleage. Testing done in Oregon found that ensiling causes certain toxins to accumulate rather than dissipate and remain at levels that are unsafe for livestock consumption.

When wheat prices and protein premiums/discounts are high, there is renewed grower interest in late N applications to enhance wheat protein. Following is an old recipe we have recently evaluated in on-farm-tests and small plot studies.

Apply 30 lb N/ac, which is 10 US gallons of UAN solution (28-0-0) diluted with 10 gallons water

Apply with flat fan nozzles

Apply 7-10 days following anthesis (so about 7-10 days after your fusarium head blight fungicide)

Apply in morning or evening when temperatures are less than 20o C. Avoid heat of the day.

Under such treatments we have observed leaf burn of 8-15% of the leaf area without detrimental impact on yield. The one instance sprayed at mid day in high temperatures reduced yields by 6 bu/ac with 31% leaf damage . Protein increase ranged from 0-1.5% and averages are reported in Table 1.

Despite rainy and windy conditions, early post-emergent herbicide applications are nearing completion in most crops. Emergence of cool season annual weeds was relatively unaffected by earlier cool, dry conditions while emergence of warm season annual weeds was delayed, resulting in herbicide staging issues for some producers. Emergence of warm season annuals, like redroot pigweed and barnyard grass, is now well underway due to recent rainfall.

Black nightshade (Solanum nigrum) is a warm season annual problematic in potato, dry bean and soybean production. What to look for: small seedlings with pointed ovate cotyledons, currently in the cotyledon to early true leaf stage (see picture submitted to MB Ag).

Galinsoga species:

Hairy galinsoga (Galinsoga quadriradiata) and smallflower galinsoga (Galinsoga parviflora) are annual species also referred to as ‘quickweed’ based on their ability to set seed within only weeks after emerging. What to look for: toothed, opposite leaves and ‘club’ shaped cotyledons (see picture submitted to MB Ag).

Oak-leaved goosefoot:

Of the various goosefoot species coming in for identification, oak-leaved goosefoot (Chenopodium glaucum) has been the most common. What to look for: goosefoot shaped leaf, often with distinct yellow-green veins. Stems may be red and green to red. Typically grows more prostrate than lamb’s-quarters. Oak-leaved goosefoot does especially well in wet and/or saline areas.

Weed Management Issues:

Manitoba Agriculture staff have begun to receive herbicide drift complaints and are providing advice accordingly. Talking to the applicator should always be the first step in a suspected drift incident. Herbicides involved in the drift complaints to date include glyphosate, group 2 and group 4 herbicides.

Many Manitoba corn fields are showing some degree of leaf purpling this spring. Here’s a quick look at why leaves turn purple and what possible causes may be.

Leaf purpling is a sign of stress. The leaves are actively producing photosynthates (sugars) but conditions are not allowing normal sugar metabolism or translocation in the plant. The purple anthocyanin pigment is associated with this sugar buildup in leaf tissue. The amount of purpling is genetically controlled, so hybrids with more of the purpling genes will appear worse than others, even though all suffer the same stress.

Common stress conditions triggering this purpling are:

Warm sunny days but cool nights (4-10oC) – this allows sugar buildup but not metabolism

Physical injury – recently wind has crimped leaf tips (Figure 4) causing sugars to buildup without being translocated to other growing parts of the plant

Purpling will often dissipate with warmer days and nights and yield loss is slight if any. But severe purpling is a symptom of crop stress, so the astute crop advisor or farmer will exploit it as a visual signal and will investigate the cause so to manage better next year.

If you have only grown glyphosate tolerant soybeans in the past, the move to conventional soybeans can offer up new challenges in regards to weed control. Good weed control is critical for maximizing yield. Here are a few quick tips:

Remember!! You can’t apply post-emergent glyphosate – Unlike glyphosate-tolerant soybeans, conventional soybeans are not a clean-up crop for weedy fields. They are a crop that needs to be planted in fields that have already been cleaned up.

Get in touch with your weed spectrum – If you have not done so already, determine what weeds are present or likely to be present in your conventional soybean fields. Are the herbicides you intend to use going to control the weed spectrum you have identified? A mismatch between weed spectrum and herbicides used is a frequent cause of weed control problems in conventional soybean fields.

Did you take advantage of pre-emergent weed control opportunities? If so, how is that working? – The advent of pre-emergent soil applied residual products has been a benefit to weed control in conventional soybeans. If this is a tool you decide to use, it is important to assess its effectiveness before you do post-emergent applications to ensure that weeds you are assuming have been dealt with have been controlled.

Amp up the Aggression!! Early and thorough weed control is key – Important regardless of the type of soybean you are growing. Research has demonstrated the critical weed free period for soybeans is emergence to the third trifoliate, where the removal of weeds provides the greatest protection of yield potential. Be timely with control and selective with products that may provide some residual control for an extended weed free period.

Know your crop growth stage, know your weed growth stage – Knowing your crop and weed growth stages as you time herbicide applications is very important in conventional soybean production. Most of the herbicides available have tighter application windows than glyphosate

Overgrown weeds are less susceptible to herbicides – this can lead to growers dishing out more money on higher cost options that might not work due to size of plants. Please take note that some herbicides can cause crop damage if they are used at the wrong growth stage. In this competitive fight for yield, you don’t want to set back your crop.

Assess the effectiveness of herbicide applications and adjust your plan – Fields should be scouted after each herbicide application to assess effectiveness. If weeds have shown up that the previous herbicide would not have controlled, you might have to change products for your next application or add extra herbicide passé. Were the weeds that you expected to be controlled, actually controlled? Don’t assume that you have dealt with target weeds until you see the evidence. These post-spraying inspections are key opportunities to detect the development of herbicide resistant weeds before they get out of hand.

Weed control in conventional soybeans is going to cost more – Seed may be cheaper, but the cost of an effective weed control program in conventional soybeans is almost always more expensive than in glyphosate-tolerant production. But remember, poor weed control remains the #1 threat to maximizing yield and profit in conventional soybeans. Weed control is a key point of investment in this crop and there are no shortcuts if the weed control situation demands action.

The future of side by side soybean fields using different herbicides is here with Xtend soybeans commercially available in 2017. Having more herbicide tools to combat the herbicide resistant weeds is important, but careful use is critical, to prevent crop damage and stay friends with our neighbors. Here are a few things to consider:

Non Xtend soybeans (and other crops) are easily damaged by dicamba – dicamba on sensitive crops always causes crop damage with very dramatic looking symptoms. As glyphosate -tolerant soybeans made up the majority of acres in the past and usually only sprayed with glyphosate, drift went unnoticed. The addition of Xtend soybeans to the cropping mix will be a reawakening to anyone who has gotten careless.

Should your pre-emergent application have been the one that included dicamba? – preferred timing for dicamba containing herbicides for use on Xtend soybeans is pre-emergent. Research has demonstrated the critical weed-free period in soybeans is emergence to the third trifoliate, early weed removal provides the greatest yield potential. Additionally, dicamba provides residual control for some weed species during that critical period. Another important point is, chances of application mistakes like drift on sensitive crops are greatly reduced during pre-emergent applications.

Only use herbicides specifically designed for the Xtend system – do not tank mix dicamba and glyphosate that you might have on hand in an attempt to make “homemade” herbicide for Xtend soybeans. The herbicide manufactured is designed specifically for use in Xtend soybeans, with reduced levels of volatilization, to prevent herbicide drift. Keep in mind the reports on the U.S. experience in 2016. Homemade concoctions are a very bad idea, plain and simple.

Use nozzles delivering extremely coarse to ultra coarse spray droplets (volume median diameter of 450 microns or more) as defined by ASABE standard S572.1 and as shown in the nozzle manufacturer’s catalog.

Do not apply:

when risk of severe temperature fall in the night;

under high humidity, temperatures above 30oC, or fog conditions, to prevent drift to sensitive crops;

when wind is blowing toward a nearby sensitive crop;

when winds are below 3 km/h or above 15 km/h.

Source: Guide to Field Crop Protection 2017 p. 163

All soybeans look alike – know what field you are in – there is no way to visually discern between the different types of soybeans. When in doubt, make sure that the applicator is in the right field. Herbicides specifically designed for the Xtend system applied to Roundup Ready or conventional soybeans will cause significant crop damage. Additionally, knowing the types of soybeans in the adjacent fields is important to indicate increased risk for off target crop damage. Remember, dry beans look like soybeans from far enough away….never make assumptions.

Sprayer cleanout requires careful attention – If producers are growing two or more types of soybeans on their farms, careful consideration has to be given to sprayer cleanout as they move between soybean fields. Even a small amount of dicamba will serve as a contaminant in the next spray load being applied, causing significant damage. Especially if you have only grown Roundup Ready soybeans in the past, recognize that the situation has gotten more complicated.

You’ve probably read about media dubbed ‘superweeds’ like glyphosate-resistant palmer amaranth and giant ragweed. Glyphosate-resistant weeds often earn this distinction because they are viewed as a greater management hardship for producers than weeds resistant to other herbicide mechanisms of actions (MOAs). And maybe rightly so. Farmers dealing with glyphosate resistant weeds elsewhere in the world have been reduced to tillage and hand rouging for weed control in some crops.

But, while glyphosate use dominates the Roundup Ready corn, soybean and/or cotton rotation in the US, group 2 herbicides play an (equally?) important role in our more diversified cropping system. For example, group 2 herbicides are used in crops like alfalfa, corn, dry beans, field pea, potato, soybean, sunflower, and in Clearfield and other group 2-tolerant crops. These herbicides are also a popular choice for group 1-resistant grassy weed control in cereals.

The point of this article isn’t to downplay the importance of glyphosate resistance but to elevate consideration of group 2 resistance. In Manitoba, over 10 weed species are known to have biotypes resistant to group 2 herbicides. And herbicide-resistant weed surveys led by AAFC indicate that the prevalence of certain species is increasing (Figure 1).

Figure 1: Prevalence of group 2 resistance in Manitoba in 2003 and 2008 as a percent of the weed species population surveyed (Beckie et al).

The following practices can help reduce the risk of developing herbicide resistant weeds and/or managing existing resistant weed populations:

If you suspect group 2 resistance in a weed species on your farm, it’s best to verify this by herbicide-resistance testing. Unfortunately there‘s no quick method – seed from the suspect population needs to be allowed to mature and collected. Samples can be submitted to AgQuest for testing in Manitoba.

In my opinion, knowing if you have group 2 resistance and assessing your risk factors is worth it. Because while glyphosate resistance is grabbing headlines, group 2 resistance may be quietly growing in your fields.

Severe winter weather can cause increased winter kill of forage stands in Manitoba. Alfalfa is prone to winterkill if the crown (the point on the plant from which all the stems grow from) is oxygen deprived due to ice cover, or if it freezes to -12 C or colder for 2-3 days.

If it is decided that a stand is sufficiently compromised that renovation is needed, some factors need to be considered. Alfalfa plants produce toxins (called medicarpins in the leaves) that reduce the germination and growth of new alfalfa seedlings. Older stands have produced medicarpins longer and therefore have more of a build up or concentration in the soil around the plant where the leaves drop to in the fall of the year. Generally the medicarpins are within 16” of the crown, so reseeding or over seeding alfalfa into these areas results in limited success.

Medicarpins break down over time, so a break from alfalfa for a year is sufficient time to allow for successful re-establish of alfalfa on that field.

Sod or no-till seeding can be a successful way of renovating old stands so long as the above information has been considered. These are some tips for successful germination and emergence of sod seeded forages.

Yield increase….not guaranteed – while strobilurin fungicides applied at the 2 to 4 leaf stage did significantly reduce the severity of the disease, yield bumps were only observed when a susceptible cultivar was grown.

Reference: Liu, C. 2014. Evaluation of fungicides for management of blackleg disease on canola and QoI-fungicide resistance in Leptosphaeria maculans in Western Canada. Master of Science Thesis. University of Manitoba. 172 pp.

If you chose a), you’d be right. Waterpod (Ellisia nyctelea L.) is an annual broadleaf plant native to Manitoba. It’s often found in shaded, wooded areas but can also thrive in ditches and agricultural fields. Our wet soils and cool spring must have provided ideal conditions for waterpod emergence as it’s being found in abundance in fields across the province.

The good news is waterpod isn’t much of agricultural pest. Although it’s an annual, it emerges and flowers early and usually dies off in June. It’s also very susceptible to glyphosate and most other burn-off and post-emergent herbicides.

Most growers will roll their beans shortly after seeding in order to prevent stones from entering the combine at harvest time and to make harvesting easier and quicker. On dry springs when soil conditions could lead to soil drifting a grower can wait and roll there beans after they are up and are at the first trifoliate stage..

When rolling after emergence

Do not roll at the Hook Stage- This is when beans are first emerging.

Do not roll in the morning wait until air temperature are around 25C before you start to roll to avoid damage to the plants.

Check for damaged plants to ensure plants are not breaking off.

If damage is too sever wait for a warmer day.

The attached video outlines some of the reminders about rolling beans.

Spruce is a common grown shelterbelt tree in Manitoba. They prefer acid soils, that are coarse textured with good drainage, have adequate water and sheltered from extreme weather conditions. If conditions are not ideal, the trees will begin to decline and become more susceptible to pests. If your trees are declining and you are considering using a fungicide/insecticide, read the label carefully to make sure the product is registered for use on the trees species and to control the pest identified. Spruce problems can be divided into three categories – Physiological, Disease and Insect.

Physiological

Winter burn or evergreen browning – caused by excessive water loss from the needles. In late winter/early spring, they take on a reddish brown appearance toward their branch tips and/or on one side of the tree. The south and southwest side may be worse due to more exposure to sun at potentially wind. If conditions are highly favorable for winter burn, buds can also lose moisture and be killed.

Natural Needle Drop – late August or early September, coniferous trees will naturally shed their older needles (usually needles which are 3 or 4 years old or older). During this process, the innermost needles will turn to yellow or brown and drop off. Although this process takes place every year, in some years it becomes more pronounced due to environmental factors. Needle loss can appear to be very dramatic and is often mistaken for a disease or insect problem. Nothing can be done to prevent natural death of needles since they do have a finite life span. Good maintenance can minimize environmental stress.

Competition Stress – if spruce are planted too close to each other, trees can suffer from competition stress. This occurs when the feeder roots from two or more trees take available water and nutrients from the same soil area resulting in slightly stronger trees taking most, while the weaker trees, deprived of water and nutrients, grow poorly and may decline and die. If the branches of two trees are in contact or intertwining, competition stress could be occurring.

Disease

Branch Canker – characterized by browning and death of entire branches. Individual diseased branches can occur anywhere on the tree, although the disease may start on lower branches and move upward. White or grayish crusty or resinous patches appear at the canker site and can also occur on the trunk. Pitch may ooze from these cankers and drip onto lower branches. During wet weather, some cankers can produce spores that disseminate to cause new infections. Pruning out areas affected is the only means of control once the disease has been initiated. Prune when the weather is dry, with pruning tools sterilized between cuts with alcohol (isopropyl alcohol), or a household disinfectant such as Pinesol or Lysol and all diseased material should be removed or destroyed.

Needle Cast – characterised by irregular tan, yellow, red-orange, reddish brown or black spots, specks or bands being produced on the needles from previous seasons of growth. The fungi can infect the new growth from the current season, but do not usually show symptoms on those needles until the following season. Affected needles generally drop early. Twigs of infected trees may appear stunted and may dieback. To prevent spreading, the new needles should be protected by applying a copper fungicide containing copper oxychloride just as growth begins in spring. Repeat applications 3 or 4 times at 10 day intervals. If the planting is not too large, it would be helpful to rake up and remove fallen needles from under the trees to remove them as a source of reinfection. There are currently no fungicides available for home use but fungicides with commercial or agricultural registration are available. Consult with an arborist or tree care service for fungicide options.

Insects

Spider Mites – all evergreen trees have a resident population, but during hot dry spells populations can explode. Visual symptoms start as dingy yellow or dusty needles and progress to brown and dry, then needles drop. There may also be a fine webbing, between the needles. In severe or prolonged infestations, dust particles, shed needles and dead mites catch in the webbing giving the tree an unhealthy appearance. Damage to the tree is caused by both adults and nymphs sucking sap from the needles. Mites can be controlled by using any insecticide listing mites and spruce on the label, at a rate recommended on the label. Dormant oil sprays can also be used to control spider mites. See directions for use on the labels.

Spruce Needle Miner –webbing is produced and may contain dead needles and frass (droppings). Damage is done after tiny larvae hatch from eggs that have been laid along the sides of a needle and begin to chew a hole at the base of it. The insects feed on the needles and exit from the same hole in search of new needles. Full-grown larvae are green with a brown head and are about 6 mm long. The larvae remain active until October when they construct a cocoon inside a nest of dead needles and frass to overwinter. Adults emerge as small greyish brown moths that have a 12 mm wingspan. If a tree has a large number of needle miner nests it can appear quite unsightly, as airborne material such as dust and poplar cotton become easily caught in them. Heavy infestations can severely weaken the tree through loss of needles. Before bud break in spring, the nests can be washed away with a strong stream of water from a garden hose. The debris should then be gathered and destroyed. This may help to reduce the current year’s infestation.

White Pine Needle Scale –evident by tiny white flecks on the needles that resemble spots of paint. Each white scale contains a dead body of a female scale insect and her overwintering eggs. During the summer the crawlers moult to become adults after which they begin to secrete a white scale covering. Scale insect feeding damage causes large yellow areas on the needles that can coalesce if the population density becomes excessively high. Sustained heavy attack for 2 or more years can cause trees to lose most of their needles. Insecticides or dormant oil sprays listing spruce and scale insects on the label can be used for control. Follow label directions.

White Pine Weevils – weevils kill the top 2-3 years growth of their host trees. Damage very conspicuous, causing the terminal leader (very top of the tree) to wilt and take on a crook shape, turn brown and die. Located below the damaged area, there can be found small exit holes made by the emerging adult weevils. Adult weevils overwinter in the litter on the ground. There are no insecticides registered for control. Prune and burn infested leaders before mid-July to remove and kill the insects. Cut back all but one live lateral (side) shoot by at least half their lengths to maintain single-stem dominance. Avoid planting the highly susceptible Colorado blue spruce in areas where white pine weevils have previously caused damage.

Spruce Bud Scale –heavy infestations can result in twig and branch dieback. The presence of sooty mold on twigs, needles and branches may be the first clue to the presence of the insect. The sooty mold does not cause any damage to the tree but is unsightly and since it is highly visible is often mistaken for the cause of needle and twig dieback if these are occurring in association with the scale infestation. The female adult scales cluster along the stems of twigs. They closely resemble the buds of the spruce tree, lower branches on the trees are often the most heavily infested. Heavy scale infestations result in discoloration and loss of needles, twig dieback, dieback of lower branches and reduced tree vigour and growth. Infested trees are also reported to be more susceptible to winter injury. Any insecticide listing spruce and scale insects on the label can be applied to reduce damage from this insect. Follow label directions. Insecticides should be applied while the crawlers are still active.

If malathion is in your shed, it may be time to revisit your inventory. According to a recent advisory issued by Health Canada (http://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2017/63150a-eng.php), Malathion products purchased prior to June 2016 should not be used. This advisory applies to all products including agricultural and mosquito control products containing malathion. The advisory was issued because over an extended period of time, malathion can convert into a toxic metabolite called isomalathion. This conversion can be faster if label directions for storage are not followed properly. If you are purchasing malathion products in 2017, be sure to check expiry date on the packaging.

What to do with old/obsolete inventory of malathion products?

Malathion products older than one year cannot be used and will need to be disposed.

If agricultural malathion products purchased prior to June 2016 are being used, users must test the product prior to use. Malathion products must be tested at an accredited laboratory and meet the requirements outlined in Health Canada Advisory. Products over a year in storage must be disposed.

Before using any product, including malathion products, confirm the registrationstatus and class of the pesticide product on Pest Management Regulatory Agency’s (PMRA) website or mobile application.

Most restricted class pesticides require a license for purchase and use. Appropriate license must be secured before using a restricted pesticide product. Farmer exemption does not apply for restricted pesticide products.

Dry spring weather is great for seeding but may play havoc with some fertilizer applications and losses.

1.Seedplaced fertilizer – Where seedbed moisture is low or when weather is hot and windy, reduce the rates of seedplaced nitrogen by approximately 50 per cent. Table 7 of the Manitoba Soil Fertility Guide http://www.gov.mb.ca/agriculture/crops/soil-fertility/soil-fertility-guide/nitrogen.html indicates safe rates of seedplaced urea under different soil texture, moisture and seedbed utilization conditions. But as conditions dry, these rates should be reduced accordingly.

2.Surface applied urea or urea-forms (like UAN solution 28-0-0) – are vulnerable to volatilization losses. The soil and environmental factors increasing risk of loss are well known and include:moist soil conditions, followed by rapid drying

high wind velocity

warm soil temperatures

high soil pH (> pH 7.5)

high lime content in surface soil

coarse soil texture (sandy)

low organic matter content

high amount of surface residue (Zero Till)

Volatilization losses can be reduced with dribble placement of UAN versus broadcast applications and the use of an urease inhibitor. The active ingredient NBPT used in Agrotain Ultra is now marketed by a number of companies. To expect the same level of protection as Agrotain Ultra, ensure the application rate is similar, since formulation strength and recommended rates differ among suppliers. Agrotain Ultra contains 27% NBPT with an application rate of 3.1 l/tonne urea or 1.6 l/tonne UAN.

3. Last year the lack of rainfall through much of May left surface applied nitrogen stranded at the surface. If possible, a portion of the crops nitrogen for cereals and canola should be in-soil placed. In season applications should be targeted prior to stem elongation of cereals and bolting of canola.

Seed can be an expensive input, but a poor crop stand can be lost profit. To maximize your seed, still get the stand needed to optimize yield, start calculating the real seeding rate needed for the plant stand desired and not gauging seeding rate by lbs/ac or bu/ac.

The following are the standard recommendations for FINAL plant stand, not what you are putting in the ground. Germination, TKW and mortality are very important to use in the equation to determine actual seeds/ac to plant. For example, if you assume your germination is 96% and its only 85% and conditions turn cold and wet (increasing mortality), you may have a lot thinner stand than you anticipated (which could mean a harder time controlling weeds).

Soil temperature drives germination and seedling emergence, so how cold is too cold? What is your soil temperature at your targeted seeding depth….today? Finally, when should you be measuring the soil temperature?

The following are the minimum temperatures needed for germination to begin in various crops. These values should be regarded as approximate, since germination depends on factors other than just temperature. But, if soils are too cool, germination will be delayed and cause uneven or poor seedling emergence.

Crop

Temperature (°C)

Wheat

4

Barley

3

Oats

5

Corn

10

Canola

5

Flax

9

Sunflower

6

Edible Beans

10

Peas

4

Soybeans

10

Sources: North Dakota State University Extension Service, Alberta Agriculture & Rural Development and Canola Council of Canada

Getting an accurate measure on soil temperature

Determine how deep you will be seeding. Then place your soil thermometer at the targeted depth. Take two measurements throughout the day: one in the morning (8am) and one in the early evening (8pm). Average the two readings to determine the average soil temperature. The recommendation is to take readings for two to three days to establish a multiple day average and to measure at a number of locations in the field, to account for field variability.

Still not sure and short on time? See the soil temperature data for various locations across Manitoba from the MB Ag-Weather Program: https://www.gov.mb.ca/agriculture/weather/soil-temperature.html. This can be used as a guideline for an area, but in-field measurements are going to tell you what is actually going on in your field!

A reminder that if seedbeds turn dry, the safety margin shrinks when applying seed placed fertilizer. Seedburn can result from ammonia toxicity and/or salt content of fertilizers.

For nitrogen, our Soil Fertility Guide provided safe guidelines for seed placed urea on cereals and canola across a range of soil types and seed-fertilizer configurations. With the increased popularity of narrow seed and fertilizer spreads with disk drills, the safe rates are reduced. For example, safe urea rates for cereals vary from 10 to 25 lb N/ac going from sand to clay soil using disk openers on 6” row spacing. These guidelines are for moist soil and should be reduced by 50% if seedbed moisture is lower when weather is hot and windy.

The safe rates of seed placed phosphorus depends on the crop, with cereals being quite tolerant compared to soybeans, dry beans and canola. With a disk drill as described above, cereals can tolerate 50 to 60 lb P2O5/ac as mono ammonium phosphate while rates would be 20 lbs/ac for canola and less for beans. If there greater seedbed utilization (i.e. narrower rows or a wider seedrow with less fertilizer concentration) rates could be more liberal.

Is it better to plant into cold soils realizing the seed is going to sit there until the soil warms up? Or should corn be planted when soil temperatures are warmer and approaching 10°C?

Planting into cold soils. Early planting is a component of successful corn production in Manitoba, to maximize yield, obtain high quality and low percent kernel moisture at harvest (which will decrease drying costs), and to ensure the crop is mature before fall frosts.

Cooler soil temperatures can delay the crop’s emergence. Wet conditions added to cold soil temperatures can favor soil pathogen development, increasing seedling disease risks in both germinating seeds and young seedlings. When planting early in the season or when the soil is cold, a planting rate 10% higher than the desired final stand should be considered to compensate for possible increased seedling mortality. As well, when planting into cool soils, other seeding management becomes important, such as good seedbed condition (good soil to seed contact) and planting operations (including planting depth).

With the wet conditions and delayed harvest experienced in parts of Manitoba in fall 2016, very few farmers were able to complete their fall fertilization program. Since early seeding is important for optimizing crop yield, producers will be looking for ways to apply their N requirements efficiently without delaying the seeding operation. In addition, soil reserves of N are variable and margins between crop revenue and input costs are modest; therefore, optimizing nitrogen fertilizer use efficiency is important. To achieve these objectives for a spring fertilization program will require use of a 4R nutrient stewardship strategy: applying the right rate of the right fertilizer source, with the right placement and at the right time to minimize losses of fertilizer N to the environment and optimize the crop’s access to the fertilizer.

The Guide to Crop Protection provides information on the use of herbicides, fungicides and insecticides for control of weeds, plant diseases and insects. This publication is only a guide. Always refer to the product label for application details and precautions. It is available: online at https://www.gov.mb.ca/agriculture/crops/guides-and-publications/#gfcp. Individual sections on Weed Control, Plant Disease Control and Insect Control can be downloaded separately. Printed guides are available for sale at Manitoba Agriculture offices.

Gravity tables and colour sorters have been shown to be an effective way of sorting out fusarium-damaged kernels (FDK) if the grower has the time and money to spend on the method. Gravity tables remove kernels based on density and are effective at removing heavily infected seeds, but can also result in the loss of healthy seed. Optical sorters remove kernels based on visual differences, but the process can be time-consuming and is more suited to hard wheat than soft wheat. Additionally, fusarium-damaged barley and oat do not show significant shrivelling and are not likely to be removed by equipment sorting by density, weight or colour.

It is important to remember that removing FDK (i.e. visibly infected kernels) from a grain sample does not mean that the grain is free of DON, the toxin produced by Fusarium graminearum. The relationship between FDK and DON varies and in years where infection occurs late in anthesis (or even after anthesis), visual symptoms are not always apparent whereas DON levels can still be elevated. While the Canadian Grain Commission grades wheat based on percent FDK, some markets are interested in DON levels. It is important to discuss with grain buyers and/or elevators their guidelines regarding FDK and DON. It is also recommended that growers test their grain for DON to best determine how to market it.

There is newer technology available that sorts grain based on chemical composition using near infrared transmission (NIR). This method is more effective at reducing DON levels because it is not only dependent on visual symptoms on the kernel. The machinery required to sort grain using NIR can be quite expensive to purchase, but is relatively inexpensive to run. For more information on this technology please refer to http://bomill.com/products/.

It’s an obvious statement to say successful farm management decisions need both agronomic and economic considerations. Farmers weigh out input cost versus the benefit to yield and quality of grain before making the decisions to buy and use new or additional products.

Agronomy and economic crop management goes much beyond inputs. Consideration of crop rotation, Cost of Production, seeding date and weather indicators for disease all need to be considered. Within agronomic decisions there can be tools to estimate the economic impacts of different decisions. The ‘My Farm’, ‘Cost of Production’, ‘Canola Reseed Calculator’ and ‘Sclerotinia Treatment Decision Tool’ are all based on yield trends and agronomy to help make economic decisions easier.

The plants on the right are redroot pigweed (Amaranthus retroflexus); the plants on the left are waterhemp (Amaranthus tuberculatus).

Unfortunately, the need to distinguish between these closely related weed species has become a reality for Manitoba producers and agronomists since waterhemp was found in the province in the fall of 2016. Suspect plant specimen collected from a soybean field in the RM of Taché was verified as waterhemp by staff with the Agriculture and Agri-Food Canada Collection of Vascular plants in Ottawa. Waterhemp occurs in neighbouring states and provinces, including Minnesota, North Dakota and Ontario.

Both species thrive in agricultural fields where they compete with crops for nutrients, moisture and light. Waterhemp has no hairs on its stem or leaves, which can be used to distinguish it from redroot pigweed when plants are small. The lack of hairs give waterhemp leaves a ‘glossy’ look unlike that of the ‘dull’ green leaves of redroot pigweed. Also, waterhemp leaves are lanceolate in shape (longer than they are wide) compared to the more ovate leaves of redroot pigweed. Colour is not a reliable identifying characteristic since both species can be green, red or variations of the two colours.

Mature waterhemp plants tend to be more branched than redroot pigweed. And unlike redroot pigweed, which has male and female flowers on the same plant, waterhemp has separate male and female plants. Waterhemp inflorescence are long, slender and vary in colour compared with the compact, prickly inflorescence of redroot pigweed. Like most pigweeds, waterhemp is a prolific seed producer with up to a million seeds per plant (under ideal conditions).

Waterhemp populations resistant to group 2, group 9 (glyphosate) and group 2+9 exist throughout the US, including Minnesota and North Dakota, and in Ontario. Seed from one of the plants found in Manitoba have been sent to Ontario for resistance testing.

Information on waterhemp will be added to Manitoba Agriculture’s weeds webpage shortly (http://www.gov.mb.ca/agriculture/crops/weeds/) and will be included at the Weed Seedling Identification Day (hosted by the Manitoba Weed Supervisors Association). Manitoba Agriculture staff will conduct a waterhemp surveillance program in and around the RM of Taché in 2017.

2015 Results. With funding from Winter Cereals Manitoba Inc., the study continued in 2015. Composite samples of eight registered winter wheat varieties were collected from the three replicates at four MCVET sites: Carman, Hamiota, Melita & Minto. BioVision Seed Labs in Winnipeg, Manitoba conducted the analysis. The level of FDK (%) was measured as per the Official Grain Grading Guide of the Canadian Grain Commission. The accumulation of DON (ppm) was measured using the ELISA test method.

The variety Emerson, rated as Resistant (R), had lower levels of FDK and DON compared to the other varieties (see Figure 1). Some varieties rated as Susceptible (S) consistently showed higher FHB severity, FDK and DON levels across all sites. However, data also shows there is variability of performance within the five resistance categories of Resistant (R) to Susceptible (S).

Figure 1: Average Levels of Fusarium Damaged Kernel (FDK) and Deoxynivalenol (DON) by Winter Wheat Variety at Four MCVET Sites in 2015

2016 Results. In the 2016 Manitoba Fusarium Head Blight Survey, the average FHB index for winter wheat was 2.7% which was slightly below the 10-year-average (3.1%). Winter Cereals Manitoba Inc. again is providing funding to have the MCVET winter wheat varieties tested for FDK and DON. Analysis is currently underway and results should be available for the Winter Cereals Manitoba Inc. Annual General Meeting on March 15, 2017.

Summary. Extensive research over the past 20 years shows using multiple management options, including crop rotation, fungicide application and variety selection, is the best way to mitigate the risk of FHB. Although FHB infection will always be highly influenced by environment, the first step is to select varieties with improved resistance and then use them in combination with other management strategies. In years where there is higher disease pressure, such as 2014, variety selection will be critical to minimize the impact of FHB on yield and quality. However, under high disease pressure yield and quality loss due to FHB can still happen in varieties that have improved resistance as resistance does not equal immunity.

Remember, caution must be used with one year of data, as presented here. Using data derived over two or more growing seasons over multiple sites is always recommended to provide the best indicator of variety performance.

The maps can be found at the link above under the heading “Thematic Crop Maps“‎. Time frame in most cases is 2006 to 2015 (10 year), but 2011 to 2015 is also available for soybean, feed wheat and corn to reflect the acreage changes that occurred in the past 5 years.

Many thanks to Doug Wilcox‎ from MASC for the database, and Les Mitchell and Natalie Azure from the Crop Industry Branch who developed and created the maps for this project.

SEED MANITOBA 2017, the Variety Selection and Growers Source Guide, is a collaborative effort between Manitoba Agriculture, the Manitoba Seed Growers’ Association and the Manitoba Cooperator. SEED MANITOBA remains one of the best sources for unbiased variety performance information with yield and quality information collected at various sites across Manitoba.

SEED MANITOBA 2017 will be available:

Local seed growers

Subscribers of the Manitoba Cooperator

Local Manitoba Agriculture Offices

A digital edition of SEED MANITOBA 2017 will also be available at www.seedmb.ca

The following link provides highlights from some of the presentations most pertinent to agronomists and farmers in Manitoba. Please contact me for further information on these presentations or meetings. Due to there being concurrent sessions at these meetings, there were many more presentations than what is presented in this summary. These were selected because of their relevance or potential interest to those working in agriculture in Manitoba. I have categorized the presentation reported by commodity group or discipline.

The information presented is a combination of material from oral presentations, poster presentations and provided as abstracts for the various symposiums. Many presentations have multiple authors, however only the presenting author is reported in this summary.

Using good quality seed, with high germinability and vigour, and low disease incidence, is always recommended. Cleaning of grain to remove fusarium damaged kernels can improve grade and seed germination. In addition, seed should be planted into warm, well-drained, fertile soil at the appropriate depth. Applying fungicidal seed treatments to cereal seed is also a beneficial management practice that helps reduce risks associated with seedling mortality and reductions in stand establishment due to seed-borne, seed-transmitted and soil-borne fungal pathogens especially when planting conditions are not optimal. Fusarium species are examples of fungi that can cause disease on germinating seeds and seedlings and reduce plant populations. The level of Fusarium infection in a seed lot should be determined by laboratory testing, not just by counting fusarium damaged kernels. In cases where Fusarium infections reduce germination, a germination test should be used to adjust the seeding rate so that emergence and yield are not compromised. Research has shown that when seeding rates are adjusted based on germination rates, seed with low levels of infection (5-10%) have no significant improvement in emergence or yield due to a seed treatment (May et al., 2010). However, it is important to keep in mind that other soil-borne, residue-borne or seed-borne microorganisms (i.e. pests other than Fusarium spp.) can also cause diseases on germinating seeds and seedlings, so even if Fusarium is not detected on seed, a seed treatment should still be considered as a beneficial risk management tool to protect against additional threats such as Pythium spp., Rhizoctonia spp., and others.

Seed treatment recommendations for each province are as follows:

Alberta

Threshold – 0%

Actions/Recommendations – Always use healthy seed with no detectable levels of F. graminearum

Always use a registered fungicidal seed treatment that includes Fusarium on the label

Actions/Recommendations – Use a seed treatment for F. graminearum infection in areas where F. graminearum is not established

Threshold – 5%

Actions/Recommendations -Do not use seed when F. graminearum infection levels exceed this threshold in areas where F. graminearum is not established

Threshold – 10%

Actions/Recommendations -Use a seed treatment when total Fusarium spp. infection levels exceed this threshold in areas where F. graminearum is established or when F. graminearum levels are less than 5% in areas where F. graminearum is not established

In Alberta, any grain with detectable levels of F. graminearum cannot be used for seed because F. graminearum is a declared pest under Alberta’s Agricultural Pests Act. Section 22c of the Agricultural Pests Act states: “No person shall for propagation purposes acquire, sell, distribute or use any seed, root, tuber or other vegetable material containing a pest.”

In Saskatchewan, F. graminearum is not a regulated pest. However, to reduce the spread of F. graminearum into areas where it is currently not established, seed containing more than 5% F. graminearum is not recommended to be used.

In Manitoba, there are no restrictions or thresholds for planting F. graminearum-infected seed. However, grain should be tested for germination and Fusarium infection before determining its suitability for seed.

The viability of various Fusarium spp. during storage is dependent on the storage conditions, with temperature playing a key role. Scientific studies have demonstrated that Fusarium infection levels will be reduced when infected grain is stored for at least 6-9 months at a constant temperature of 25 °C and where either relative humidity is >62% or seed moisture content is at least 10-14%. One study demonstrated elimination of Fusarium graminearum when corn seed was stored in sealed containers at 30°C and a seed moisture content of 14%. However, the same is not true for infected grain stored at cooler temperatures (less than 15°C) which are more consistent with the recommendations for grain storage on the Canadian Prairies. At temperatures below 15C the viability of the pathogen (Fusarium spp.) is unchanged, unchanged, especially under drier conditions, making long term storage of infected grain a poor strategy for reducing Fusarium infection levels. Also, if the grain is to be used for seed, prolonged storage of infected grain at higher temperatures and moisture levels may result in reduced vigour and germination rates.

The mycotoxin deoxynivalenol (DON) in Fusarium infected grain is also unaffected by long-term storage, regardless of the temperature. Under safe storage conditions changes in DON levels would be unlikely.

Deoxynivalenol (DON) is a mycotoxin produced by the fungus that causes fusarium head blight (FHB). The importance of determining DON levels in your harvested grain relates to the use of that product for human/animal consumption. DON is poisonous to humans so it is carefully monitored in grain used for food. Additionally, it is poisonous to livestock and can cause feed refusal and poor weight gain in livestock if present above recommended levels.

The relationships between fusarium-damaged kernels (FDK), seed infection by Fusarium spp., and DON levels are not consistent. Just because FHB was observed in the field and/or FDK were observed in a harvested sample it does not necessarily mean that DON is present. Conversely, the lack of these symptoms does not necessarily mean that DON is not present. The latter situation is often the case in years where conditions are conducive for Fusarium infection after anthesis. These DON levels are not accounted for when grading grain is based solely on the percentage of FDK.

While DON levels may affect the suitability of harvested grain as food or feed, seedling health and seed germination is affected by the extent of infection of seed by hyphae of Fusarium graminearum. Thus, the level of infection by Fusarium spp., including F. graminearum, is a better measure of whether or not the grain should be used for seed in a subsequent season.

Recommendations:

For purposes of replanting, growers should have seed tested by an accredited lab for germination, vigour, and Fusarium infection levels. Based on this information growers can determine whether or not a grain sample is appropriate for planting (with or without a seed treatment) and whether the seeding rate would need to be adjusted. (See future questions in this series that will address whether or not to plant Fusarium-infected seed.)

For purposes of marketing and livestock feeding, growers should have grain tested for DON levels by an accredited lab. Grain companies and buyers are increasingly requesting information on DON levels as opposed to just FDK.

Fusarium head blight, or FHB, is a major disease that wheat and other cereal producers deal with each year to varying levels. The conditions in 2016 were conducive for infection in both winter and spring wheat as well as other cereal crops (symptoms were observed in both barley and oats). While 2016 was not the worse year on record for FHB in Manitoba (see post on FHB survey results), levels across the prairies were amongst the highest they have been in recent years.

Manitoba Agriculture has partnered with Alberta Agriculture and Forestry and the Saskatchewan Ministry of Agriculture to develop a Q & A series “Getting the Facts on Fusarium Head Blight”. This series will address FHB issues producers faced in the 2016 season as well as issues they are facing regarding infected seed. The answers provided will be a combined effort of the provincial disease specialists with input from researchers at Agriculture and Agri-Food Canada, the University of Saskatchewan, and the University of Manitoba.

If you have a question you would like to see addressed please submit via Crop Chatter or contact your provincial disease specialist.

The following are the results of spring and winter wheat fields surveyed for Fusarium head blight (FHB) by Manitoba Agriculture Staff. Fusarium head blight was observed in nearly every field surveyed (97% of winter wheat fields surveyed and 93% of spring wheat fields surveyed). The average FHB index for winter wheat in 2016 was 2.7% which was slightly below the 10-year-average (3.1%). The average FHB index for spring wheat in 2016 was 2.4% which was slightly above the 10-year-average (2.2%).

The most common question I receive over the winter months related to winter wheat production is “How is the cold weather/warm weather/lack of snow impacting my winter wheat?” Unfortunately, there are no easy answers over the winter months as we typically have to wait until spring when winter wheat breaks dormancy and stand establishment is known.

However, there can be a few key factors during fall establishment and weather conditions over the winter months that can provide guidance in terms of assessing weather and its impact to Manitoba’s winter wheat prior to the crop actively resuming growth next spring.

First step: record crop condition prior to winter. The crop stage and health/vigour of the crop as it heads into winter will provide an indication if the crop has a high chance of surviving the winter with minimal winterkill or winter injury. Ideally plants should be at the 3 leaf to 1 tiller stage and have well-developed crown tissue (and of course established into adequate standing stubble to ensure snow catch). And remember, the stage of crop development in the fall influences not only winter survival, but also yield potential, crop competitiveness, maturity and the risk of infection with diseases such as rust and fusarium head blight.

Second step: note the weather after seeding and prior to winter. Cool conditions in the fall where plants grow for 4 to 5 weeks, followed by 4 to 8 weeks (October to November) of growth that allow plant to acclimate and vernalize, is the ideal situation (relates back to an optimum seeding date of the first couple weeks of September). Read more about cold acclimation and vernalization here: http://cropchatter.com/winter-wheat-survival-impacted-by-fall-management-decisions-the-weather/. Another key weather factor is open field conditions with little or no snow cover until freeze-up as this allows soil temperatures to gradually decline to freezing levels.

Third step: record any weather stresses over the winter months. In the fall, winter wheat producers can take all the necessary steps to set their crop up to survive winter with minimal winterkill or injury. However, it is often the winter/early spring weather in Manitoba that can impact winter survival. Producers should take notes of cold snaps (how long they lasted, when did they occur) and the snow cover during those events to gauge potential impact to their winter wheat crop.

Regardless of the amount of cold acclimation, we typically need to receive good snow cover to protect the crop from the sustained cold temperatures normally seen in January and February in Manitoba. The ideal situation would be a minimum of 4 inches of trapped snow cover through December to early March to buffer soil temperature changes and provide protection to the crown tissue.

Over the past three winters, Manitoba Agriculture through the AgWeather Program has been measuring soil temperatures real-time in winter wheat fields. The monitoring of soil temperatures can provide an early indication if there is a concern for winter injury or winterkill. The earlier a problem is identified or suspected, we are able to provide that information to industry so careful assessment of acres occurs in the spring.

There are 4 Manitoba Agriculture AgWeather Program weather stations measuring real time soil temperatures in winter wheat fields. The sites are at Crystal City, Kleefeld, Oakburn and Virden. Bookmark the link: ftp://mawpvs.dyndns.org/Tx_DMZ/WWST2016_17.png

Long Answer: Normally in Manitoba, the majority of our inoculum blows in from the central US states by what is known as the “Puccinia Pathway”. However, according to Dr. Brent McCallum, a Research Scientist with AAFC in Morden, MB, there was evidence of both stripe and leaf rust overwintering on winter wheat in Manitoba a few years ago but at such low levels it wasn’t a concern. Dr. Kelly Turkington, a Research Scientist with AAFC in Lacombe, AB, also indicated overwintering of stripe rust occurred in Alberta and parts of Saskatchewan in 2010/11 where there were measurable losses. In that particular year, there was a breakdown of resistance in the 2010 planted winter wheat crop and that led to higher infections into 2011.

So yes, stripe rust can overwinter. However, the ability of stripe rust to overwinter in Manitoba, or elsewhere, would depend on factors such as the severity of the winter and snowfall amounts.

If stripe rust is seen in the fall, take note of the variety and its resistance rating. Although nothing can be done about variety selection at this point, in the future consider stripe rust resistance when evaluating and selecting winter wheat varieties. Genetics….it’s a fast and easy way to protect your crop from disease pressure!

If winter weather conditions allow for overwintering of stripe rust, it could provide a local source of inoculum early in the spring – as early as the crop starts actively growing. A cool, wet spring could also favor spread and infection of stripe rust, not only to winter wheat but to other crops such as spring wheat.

If you do see stripe rust this fall in your winter wheat crop, mark those fields as ones to watch as soon as the crop breaks dormancy next spring. If stripe rust does overwinter, a fungicide application may be necessary.

Should a fall fungicide application be considered?

There has been some recent research conducted looking at the yield response and economics of a fall fungicide application in winter wheat. From 2011 to 2013, researchers from AAFC conducted a study across Western Canada looking at a variety of management factors, including one looking at a fall fungicide application. Results were recently reported in Top Crop Manager at http://www.topcropmanager.com/business-management/improving-winter-wheat-19554. The following statements are from the article.

In regards to the fall fungicide treatment, “the study showed some benefit from the fall foliar fungicide treatment, however the increase was small and resulted in decreased net returns,” says Turkington (who was involved with the study). “In areas with confirmed stripe rust in the fall, the yields gains were a bit better. However the cost of application is prohibitive at this point compared to no application. ”

More research is currently underway by Turkington and Dr. Randy Kutcher (University of Saskatchewan) looking at a fall fungicide application, a spring fungicide application at flag leaf emergence, and a dual application (one in the fall and one in the spring). “The preliminary results after the first two years aren’t showing much of a benefit from the fall foliar fungicide application, similar to our recent study,” Turkington says. “Some of the results suggest a dual fall and spring application does not provide any additional benefit over a spring application in Western Canada.”

So for this fall, don’t pull out the sprayer if you see stripe rust in your winter wheat. But, be ready to scout in the spring! And look for more updates to current winter wheat research underway across Western Canada.

Do you have weeds that survived this year’s herbicide application(s)? Since there are many factors that can contribute to weed escapes, consider:

The distribution of escaped weeds. Herbicide-resistant weeds tend to occur in patches as opposed to geometric patterns (e.g. spray miss) or throughout the field (e.g. tolerant weeds).

Possibility of reduced herbicide efficacy. 2016 was a challenging year for weed management due to untimely and excessive rainfall. In many cases, weeds escaped because of herbicide application timing with respect to weed growth stage, limited herbicide choices because of crop growth stage (when producers finally could get on their fields) and product rainfastness.

Weed species. Annual weed species, like wild oat, green foxtail, cleavers, kochia, hemp-nettle, smartweeds, ragweeds and wild mustard, may be more likely to develop resistance compared with other weed species. Because the development of herbicide-resistance is based on chance, resistant weed patches are typically a single species, as opposed to non-resistant weed escapes, which may affect multiple weed species.

Suspect weed escapes can be confirmed as resistant or susceptible by herbicide-resistance testing. For most weeds, dry, mature seed is required for the analysis. Although more is better, many labs require at least 100 g of small weed seeds (e.g. cleavers) and 200-250 g of large weed seeds (e.g. wild oat). Weed seed samples should be submitted by December 31st, 2016 to either:

For suspected glyphosate-resistant kochia, a genetic-based tissue test is also available from the Pest Surveillance Initiative: http://www.mbpestlab.ca/field-testing/. In this case, about 5 to 10 g of green plant tissue (e.g. leaves and stems from plant tips) is needed for the analysis. Samples should be placed on ice and shipped immediately after collection. The advantage of the genetic test (vs. seed analysis) for kochia is the ability to determine resistance in-season.

Goss’s Wilt was reported in several areas of Manitoba during the 2016 growing season. Goss’s Wilt is a bacterial disease and CANNOT be controlled by a fungicide. Managing Goss’s Wilt include weed control, tillage and most importantly rotation and hybrid selection (genetics!). And with the seed ordering season quickly upon Manitoba corn growers, here are 3 questions you should ask your seed dealer about Goss’s Wilt ratings. The more information you have, the more informed decision you can make.

But before that, some key points:

there is no third party data available for Manitoba hybrids;

ratings will likely change over time as more years of testing are completed, in different locations and conditions;

resistance does not equal immunity! Plants don’t have immune systems and therefore can’t be immune to any disease. Depending on the level of disease pressure, hybrids that are rated as resistant/tolerant can still be infected to some degree. If disease pressure is high (i.e. high inoculum levels, conducive environmental conditions for a long period of time), yield loss due to Goss’s Wilt can still occur in the best rated hybrids.

But First! Before you start asking your seed dealer questions, if you experienced Goss’s Wilt this year perhaps there’s a few questions you can ask yourself (or your neighbor if they had Goss’s Wilt). Was Goss’s Wilt present in every corn field, just one or a few? What were the levels of Goss’s Wilt in individual fields? Do you (or your neighbor) know the resistance rating of those hybrids, both exhibiting symptoms or not exhibiting symptoms? Are you keeping good field notes? While there is no third party data available, you could start making subjective on-farm comparisons (but at the same time recognizing the limitations of those comparisons).

Question 1: What is the rating scale used? Since there is no universal system for determining Goss’s Wilt ratings in Manitoba, there can be differences between companies and their hybrid ratings. For some companies, a rating scale of 1 to 9 is used, where 1=Poor and 9=Excellent. However, other companies use the same 1 to 9 scale, but 1 = Resistant and 9 = Susceptible. Then there are others that only use a 1 to 5 scale. So read the fine print….what does a 3 really mean? And remember, since there is no universal system in Manitoba, you can only really compare between hybrids within a single company.

Question 2: How is the testing done to establish the ratings? Ask if the testing is done under natural infection or through disease nurseries with inoculation. Relying on natural infection to determine ratings is not as dependable as disease nurseries with inoculation (and wounding). Goss’s Wilt typically shows up in patches and can be very weather –dependent. Also, Goss’s Wilt needs an entry point, often caused by hail, wind damage, etc. No symptoms under natural infection may not indicate resistance, but instead conditions weren’t conducive for infection, i.e. escape. Artificially inoculated nurseries may be resource intensive, but provide a better chance for determining resistance levels of hybrids being evaluated.

Question 3: Where is the testing done to establish the ratings? For some companies, testing is done in the United States, while other companies have established trials in Manitoba. Why would this be important? There is variability in the pathogen population, where strains are separated into groups based on DNA analysis. Further research is on-going at the University of Manitoba with funding provided by the Manitoba Corn Growers Association and Growing Forward 2 to determine the strains of Goss’s Wilt present in Manitoba. We are only beginning to understand the pathogen population here in Manitoba so there is more research that needs to be done to fully understand the role of host resistance. In the meantime, testing conducted with disease nurseries and inoculation, either here or elsewhere, is a good step to provide information on hybrid resistance ratings.

Remember, resistance ratings to Goss’s Wilt is only one of many hybrid characteristics producers should consider when choosing their hybrid!

Over the past few weeks, we’ve heard about the impact of the poor weather conditions over the harvest period on the quality of harvested grain. With the crop off the field and into the bin, marketing now becomes the focus of many producers.

In the attached article (updated from 2014) by Gary Smart, Farm Management Specialist with Manitoba Agriculture, he provides excellent information to cope with downgraded crops. Some highlights include:

When marketing poor quality grain, be prepared and don’t panic, especially right at harvest time.

Know the quality and find a buyer who will offer the best value.

Take good samples. Without thorough samples, it is tough to know what is actually in the bin.

Communicate with the buyer if already some of this year’s crop is already contracted.

Unless cash flow is an issue on the farm, being patient could be the best action to take as new markets may arise for poor quality grain.

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Reference material

Diseases: New clubroot cases have been confirmed in the Rural Municipalities of Lorne and Dufferin. Insects: Scouting for bertha armyworm continues with some reports of insecticide applications. Spider mites being noticed in some soybean fields. Grasshopper populations are variable. For full report see Insect & Disease Report – August 1, 2018

Crops are advancing rapidly with the warm and dry conditions. Rain is needed in most areas to sustain crops and replenish soil moisture. Harvested has started in winter cereals, barley, and peas. Swathing or pre-harvest applications have started in early seeded spring cereals and canola. Fist cut hay is nearing completion; yields are below normal. […]

Diseases: The second case of clubroot in canola this year has been reported. Disease surveys in soybean and wheat are ongoing and disease levels are low overall. Insects: Overall insect concerns in field crops are relatively low. There are still some areas where grasshopper levels are being watched. Spider mite levels are being monitored in some soybean fields in […]

Disease – Goss’s wilt was observed near St. Claude. Insects – Grasshopper populations are being monitored in and around the edges of some fields. Armyworms have been noticed in some cereal fields in the Central and Eastern regions. No soybean aphids have been reported yet. For more details and information see http://www.gov.mb.ca/agriculture/crops/seasonal-reports/manitoba-insect-and-disease-update-2018-07-11.html

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News releases

Favourable weather and field conditions have allowed seeding operations to begin, with a provincial estimate of <5% of the 2017 crop seeded. For the full crop report, see on-line at http://www.gov.mb.ca/agriculture/crops/seasonal-reports/crop-report-archive/crop-report-2017-05-01.html

The Guide to Crop Protection provides information on the use of herbicides, fungicides and insecticides for control of weeds, plant diseases and insects. This publication is only a guide. Always refer to the product label for application details and precautions. It is available: online at https://www.gov.mb.ca/agriculture/crops/guides-and-publications/#gfcp. Individual sections on Weed Control, Plant Disease Control and Insect […]

Did you know you can view the 2017 edition of Seed Manitoba, as well as past editions, on www.seedmb.ca? Well, you can! Flip-view digital editions of the current guide (2017), as well as the six most recent editions, are available at http://www.seedmb.ca/digital-edition/. Also, full PDF versions are available at http://www.seedmb.ca/digital-edition/pdf-editions-and-separate-section-pdfs/ where you can download the entire […]

http://www.gov.mb.ca/agriculture/crops/plant-diseases/clubroot-distribution-in-manitoba.html Map shows positive clubroot findings by Rural Municipality, discovered through laboratory testing for presence of clubroot spores in soil and/or positive confirmation of clubroot symptomatic plants. Testing was done from 2009-2014 and is still considered limited. Positive findings have been at low spore concentrations and sporadic throughout the province. As more fields are sampled, the map will be updated. As less than […]